LXR linux/arch/arm/mach-bcm/board

   1/*
   2 * Copyright (C) 2014 Broadcom Corporation
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public License as
   6 * published by the Free Software Foundation version 2.
   7 *
   8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
   9 * kind, whether express or implied; without even the implied warranty
  10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 * GNU General Public License for more details.
  12 */
  13
  14#include <linux/of_address.h>
  15#include <linux/of_platform.h>
  16#include <linux/io.h>
  17
  18#include <asm/mach/arch.h>
  19
  20#include "kona_l2_cache.h"
  21
  22#define RSTMGR_DT_STRING                "brcm,bcm21664-resetmgr"
  23
  24#define RSTMGR_REG_WR_ACCESS_OFFSET     0
  25#define RSTMGR_REG_CHIP_SOFT_RST_OFFSET 4
  26
  27#define RSTMGR_WR_PASSWORD              0xa5a5
  28#define RSTMGR_WR_PASSWORD_SHIFT        8
  29#define RSTMGR_WR_ACCESS_ENABLE         1
  30
  31static void bcm21664_restart(enum reboot_mode mode, const char *cmd)
  32{
  33        void __iomem *base;
  34        struct device_node *resetmgr;
  35
  36        resetmgr = of_find_compatible_node(NULL, NULL, RSTMGR_DT_STRING);
  37        if (!resetmgr) {
  38                pr_emerg("Couldn't find " RSTMGR_DT_STRING "\n");
  39                return;
  40        }
  41        base = of_iomap(resetmgr, 0);
  42        if (!base) {
  43                pr_emerg("Couldn't map " RSTMGR_DT_STRING "\n");
  44                return;
  45        }
  46
  47        /*
  48         * A soft reset is triggered by writing a 0 to bit 0 of the soft reset
  49         * register. To write to that register we must first write the password
  50         * and the enable bit in the write access enable register.
  51         */
  52        writel((RSTMGR_WR_PASSWORD << RSTMGR_WR_PASSWORD_SHIFT) |
  53                RSTMGR_WR_ACCESS_ENABLE,
  54                base + RSTMGR_REG_WR_ACCESS_OFFSET);
  55        writel(0, base + RSTMGR_REG_CHIP_SOFT_RST_OFFSET);
  56
  57        /* Wait for reset */
  58        while (1);
  59}
  60
  61static void __init bcm21664_init(void)
  62{
  63        of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
  64        kona_l2_cache_init();
  65}
  66
  67static const char * const bcm21664_dt_compat[] = {
  68        "brcm,bcm21664",
  69        NULL,
  70};
  71
  72DT_MACHINE_START(BCM21664_DT, "BCM21664 Broadcom Application Processor")
  73        .init_machine = bcm21664_init,
  74        .restart = bcm21664_restart,
  75        .dt_compat = bcm21664_dt_compat,
  76MACHINE_END
  77